Show military time (24 hours) in the system clock in Windows 7

By default (for a computer purchased in the US anyway), Windows 7 displays the clock's time in a 12-hour format, using the "AM" or "PM" suffix to indicate whether it is the night / morning or afternoon / evening. But Windows 7 does support so-called "military time", where the time of day is shown in a 24-hour format. In this tutorial, you will learn how to configure Windows 7 to show military time instead of AM/PM in the system clock and the rest of programs (most applications, even created by third-party developers, respect your operating system's "regional settings", and will display date and time in the format set in your global preferences).

Change time format to military time in Windows 7

Follow these steps to start using a 24-hour time format instead of AM/PM:

Open the start menu, and type "time format" in the search field.

Windows 7 will load (probably as the two first search results) a "Change the date, time, or number format", and "Change the way time is displayed" - click on either of these links, they will both load the "Region and Language" settings dialog.

Make sure that the "Formats" tab is selected; Windows 7 can use two format versions of the time in clocks, calendars, and other pieces of software that tap into your operating system's regional settings: "Short time" and "Long time" - this of course means that you can have 24-hour based military time for one time format, and the 12-hour AM/PM format for the other time.

To change to military time in the system clock, modify the value inside the Long time dropdown from its current setting to "H:mm:ss", if you are ok having 3 or 4 digits representing the time; if you want to have Windows 7 always show 4 digits (adding a zero in front of a one-digit hour if needed), choose "HH:mm:ss" instead. (Make sure that you choose the values with uppercase letter "H", which represents 24-hour time format, or military time).

If you want to use military time everywhere in Windows 7, change the option you have under the Short time dropdown menu as well to one of the two 24-hour formats.

Click on the OK button to apply your new setting and return to Windows.

You have successfully changed your time format to military time!

Note: Keep in mind that (if you are in the US or Canada, or are dealing with North-Americans), most people aren't familiar with the 24-hour time format, so you may need to manually "translate" your timestamps in some documents to use the AM/PM, 12-hour time format.